Bigelow



J. K. BiGELOW.

Watch Stop.

Patented Feb. 8, 1859.

UNITED STATES PATENT OFFICE.

JOHN K. BIGELOIV, OF \VALTHAM, B'IASSAOHUSETTS, ASSIGNOR TO APPLETON, TRACY & COMPANY, OF SAME PLACE.

MECHANISM FOR STOPPING WATCHES.

Specification of Letters Patent No.

To all whom it may concern:

Be it known that I, JOHN K. BIGELOW, of \Valtham, in the county of MiddleseX and State of Massachusetts, have invented an Improved Stop Motion or Mechanism for a atch or Timepiece, and do hereby declare that the same is fully described and represented in the following specification and the accompanying drawings, of which- Figure l, is a plan of the same in its application to the pillar plate of a watch; Fig. 2, is a view of the opposite or potence plate, and the hair spring balance thereof; Fig. 3, is a transverse section taken through the stop of the balance.

In such drawings, A, denotes the pillar plate, or that next which the dial plate is generally fastened, while B, is the potence plate, on the back of which is the balance wheel C, connected with the hair spring D, and applied to the said potence plate in the ordinary manner. Underneath or near the balance wheel as shown in the drawings, the plates, A, B, are furnished with slots, (no for the reception of the stopping stud 0, which projects through them from a stop lever E, and alongside of the periphery of the balance wheel C. The said stop lever E, formed as shown in Fig. 1, turns on a fulcrum or screw (Z, and has a spring 6, applied to it and the plate A, in such manner as not only to force the stud, c, of its stop gear arm toward the balance wheel, but also to press the shorter arm of the lever against the notched periphery of a ratchet, F. This ratchet has each tooth f, formed with a notch or space, g, (see Fig. 4, which exhibits the ratchet on an enlarged scale) the tooth being formed of a trapezoidal shape and the notch being arranged in it as shown in the said figure.

From the above it will be seen that by such a construction of the ratchet it becomes furnished with two series of notches 6, g, g; n, a, n, on its periphery, each notch of one series being of a greater depth, than each notch of the other series, and every notch of one series being arranged immediately between two next adjacent notches of the other series. Against the periphery of the said ratchet, an impelling pawl G, carried by a thumb slide H, is arranged as shown in the drawings, the said slide H, being placed in the rim I, of the watch case and so applied thereto as to project outwardly 22,914, dated February 8, 1859.

therefrom and be capable of sliding longitudinally therein. The impelling pawl is jointed to the slide, and has a spring, K, applied to it so as not only to press it backward in a longitudinal direction but toward the ratchet wheel at one and the same time. Thus, the spring performs two functions.

In the operation of the before described stop motion, the ratchet wheel will be moved or turned a short distance on its arbor, Z, by the act of forcing inward its thumb slide, H, the impelling pawl during its retraction being forced to slip from a smaller to a larger notch, or vice versa, according to circumstances. IVhen the stop lever E, is in any one of the larger notches of the ratchet, its stopping stud 0, will be against the periphery of the balance wheel so as to arrest the motion of the said balance wheel. So, when the stopping lever is in one of the smaller notches, the stopping stud will be off the balance wheel or not against it. Therefore, if when the watch is going, a person should desire to stop it, he must press the thumb slide inward, and whenever he may desire to put the watch in motion again, he has only to force inward again the said thumb slide, the peculiar mode of constructing the ratchet enabling these operations to be carried on as described.

The above described stop motion is very simple in its construction. In this its peculiar merit is to be found. Furthermore, by means of it, we can both stop and start the watch by pressing inward the thumb slide, one inward movement of it sufiicing to stop the watch, and the next to relieve the balance wheel so as to enable it to vibrate.

I am aware of the nature of the stop motion used in the independent timer, or watch made by Jules Emmery of Sagre in which case the stopping and the starting of the second hand is effected by consecutive movements of the thumb rest or slide and two separate ratchets, and separate pawls are employed to those ratchets. Therefore I do not claim such. My invention or improvement is much more simple in construction and operation and is intended, particularly for stopping the watch by arresting the motion of its balance. Instead of two separate ratchets, placed one above the other, I make use of but one, and employ but one stop pawl which not only performs the function of arresting the motion of the ratchet but that of carrying the stopper of the bal ance.

I claim 1. The peculiar mode of making the 5 ratchet, viz., With trapezoidal teeth and with a notch in each of them as described and represented.

2. I also claim the arrangement or application of the stop lever E, With respect to 10 the stopping stud and the ratchet, or so as to serve not only as a carrier, and actuator of, the former but as a stop to the latter under circumstances as above specified.

In testimony whereof I have hereunto set my signature.

J. K. BIGELOW.

l/Vitnesses J ONAH BUTTER, R. E. ROBBINS. 

